* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

.slider {
    position: relative;
    width: 100%;
    max-width: 100%;
    /* prevent overflow */
    margin: auto;
    overflow: hidden;
}

.slides {
    position: relative;
    width: 100%;
}

.slides img {
    position: absolute;
    width: 100%;
    height: auto;
    /* keep image aspect ratio */
    left: 0;
    top: 0;
    opacity: 0;
    transition: opacity 1s ease-in-out;
}

/* active image will be shown on top */
.slides img.active {
    opacity: 1;
    position: relative;
    z-index: 5;
}

/* Navigation buttons */
.prev,
.next {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 0, 0, 0.5);
    color: white;
    padding: 10px;
    cursor: pointer;
    border: none;
    font-size: 18px;
    z-index: 10;
}

.prev {
    left: 10px;
}

.next {
    right: 10px;
}

/* Top right button */
.top-btn {
    position: absolute;
    top: 30px;
    right: 30px;
    background: #ff5722;
    color: #fff;
    border: none;
    padding: 10px 20px;
    font-size: 16px;
    border-radius: 6px;
    cursor: pointer;
    z-index: 20;
    transition: background 0.3s ease;
}

.top-btn:hover {
    background: #e64a19;
}